I documented this years ago. I release it now, as people seem to be interested. This document is about detailed changes from version to version of id's original executables as well as the resource WAD's....

This FAQ is for people having trouble finding the Keys on different
levels of ID software's game; DOOM ][. This document does _not_ cover
how to get the Keys in any other version of DOOM nor any of the freely
available DOOM pWADs. ...

A wide-ranging FAQ covering all aspects of The Master Levels. This HTML document used to be at http://hjem.get2net.dk/henriklarsen/master.htm I (the uploader) obtained this copy via the Internet Archive (http://www.archive.org)....